Before sealing your ducts, you’ll need to select the right material for this important home maintenance job. It’s now possible to select an advanced duct-sealing material, ensuring a long-lasting, tightly sealed duct system. With efficient ductwork, homeowners experience improved comfort and lower energy bills. There are two basic options when it comes to choosing materials for sealing your ducts: mastic sealant and tape. Learn the pros and cons of each.